Washing machine agitator having helical rib and method for using same

ABSTRACT

A washing machine includes a washing machine cabinet. A wash basket is mounted within the washing machine cabinet. A first agitator is mounted in the basket for rotation about a first agitator axis that extends in a direction different from the rotational axis of the wash basket. First agitator includes a first helical rib thereon for engaging and agitating the materials to be washed within the wash basket. A second agitator with a second helical rib may also be contained within the wash basket.

BACKGROUND OF THE INVENTION

[0001] This invention relates to a washing machine agitator having a helical rib and a method for using same.

[0002] U.S. Pat. Nos. 5,829,277 and 6,220,063 both disclose a washing machine having a spherical basket for containing the fabrics to be washed. In the spherical basket are a pair of circular concave agitators nested against the opposite side walls of the spherical agitator basket.

[0003] In order to achieve satisfactory cleaning of the fabrics being washed, it is desirable to achieve “turn over” of the fabrics being washed. The two agitators accomplish this by lifting the fabrics and causing them to be dropped downwardly towards the center of the washing basket. It is therefore desirable to provide agitators having the capability of lifting the fabrics during their rotation so that the fabrics are lifted up and dropped down the center to achieve the turn over necessary for satisfactory cleaning.

[0004] Therefore a primary object of the present invention is the provision of an improved washing machine agitator having a helical rib.

[0005] A further object of the present invention is the provision of a washing machine agitator having a helical rib which commences at an inner central point adjacent the rotational axis of the agitator and progresses helically and radially outwardly therefrom to an outer edge.

[0006] A further object of the present invention is the provision of a spiral rib or baffle which smoothly engages the fabrics near the center of rotation of the pan and as the pan rotates the engagement point increases in radius.

[0007] A further object of the present invention is the provision of a washing machine agitator having a helical rib or baffle that gives the fabrics being washed a smooth application of force to turn the load over with a minimum of tangling.

[0008] A further object of the present invention is the provision of a washing machine agitator having a helical rib with two tapered surfaces which are joined along a helical ridge, one of the surfaces having a sharper angle of inclination than the other of the surfaces.

[0009] A further object of the present invention is the provision of an improved washing machine agitator that is economical to manufacture, durable in use, and efficient in operation.

BRIEF SUMMARY OF THE INVENTION

[0010] The foregoing objects may be achieved by a washing machine comprising a washing machine cabinet. A wash basket is mounted within the washing machine cabinet for rotation about a wash basket axis. The wash basket includes an opening for placing materials to be washed within the wash basket.

[0011] A first agitator is mounted in the basket for rotation about a first agitator axis that extends in a direction different from the wash basket axis. The first agitator includes a first helical rib thereon for engaging and agitating the materials to be washed within the washing basket when the first agitator is rotating about the first agitator axis.

[0012] According to another feature of the invention, a second agitator is mounted within the basket for rotation about a second agitator axis extending in a direction different from the wash basket axis and the first agitator axis. The second agitator includes a second helical rib thereon for engaging and agitating the materials to be washed within the wash basket when the second agitator is rotating about the second agitator axis.

[0013] According to another feature of the invention the first and second agitators each include a concave surface and the first and second helical ribs protrude from the concave surfaces of the first and second agitators respectively.

[0014] According to another feature of the invention an agitator drive mechanism is connected to the first and second agitators for driving first and second agitators in opposite rotational directions.

[0015] According to another feature of the present invention, the first and second helical ribs extend in first and second helical directions that are opposite to one another.

[0016] According to another feature of the present invention each of the first and second helical ribs commence adjacent the first and second agitator axes respectively and extend in an outward radial helical direction therefrom.

[0017] According to another feature of the present invention, the basket includes a concave interior surface and each of the first and second agitators include a convex surface opposite from the concave surface thereof. The convex surfaces of the first and second agitators face toward the concave interior surface of the basket.

[0018] According to the method of the present invention, the fabrics being washed are lifted with the first and second helical ribs on the first and second agitators during rotation of the first and second agitators about the first and second agitator axes respectively. The helical ribs then drop the fabrics after they lift the fabrics whereby the fabrics will turn over and fall into the center portion of the basket.

[0019] According to another feature of the method of the present invention, the first and second agitators are rotated in first and second opposite rotational directions.

[0020] According to another feature of the method of the present invention, the rotational directions of the first and second agitators are reversed.

[0021] According to another feature of the present invention, each of the first and second helical ribs include first and second side walls which angle toward one another and are joined together at an elongated helical rib. The first side wall has a first angle of inclination and the second side wall has a second angle of inclination that is steeper than the first angle of inclination. The method further comprises rotating the first and second helical ribs about the first and second agitator axes respectively in a rotational direction that causes the first side wall of the first and second helical ribs to engage and lift the fabrics.

[0022] According to another feature of the present invention the rotational directions of the first and second helical ribs are reversed so that the second side walls of the first and second helical ribs engage and lift the fabrics.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023]FIG. 1 is a perspective view of the washing machine of the present invention.

[0024]FIG. 2 is a vertical sectional view of the washing machine shown in FIG. 1.

[0025]FIG. 3 is a perspective detail showing one of the agitators and the gear mechanism for rotating the agitator.

[0026]FIG. 4 is a perspective view of one of the agitators of the present invention.

[0027]FIG. 5 is a perspective view of the second of the agitators of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0028] Referring to the drawings the numeral 10 generally designates the washing machine of the present invention. Washing machine 10 includes a cabinet 12, a control panel 14, an access opening 15 (FIG. 2), and a door 16 which is hinged to move from an open to a closed position over the access opening 15.

[0029] Mounted within the lower end of cabinet 12 on a web 23 is a reversible motor 18 of conventional construction. Motor 18 has an output shaft 20 which extends upwardly through a bearing 22 in the web 23. Motor 18 is attached to the web 23 by brackets 24. Shaft 20 extends upwardly through a clutch 26 shown schematically in FIG. 2. Clutch 26 is adapted to respond to rotation of the shaft 20 in a first direction to drive a hub 34 which is connected to a spherically shaped basket 40. Rotation of the shaft 20 in the opposite direction disengages the clutch and permits the shaft 20 to rotate independently of hub 34.

[0030] A tub 28 includes at its lower end a basin 30 for holding washing fluid. Extending upwardly from basin 30 is a spherically shaped lower tub portion 31. The tub 28 extends upwardly to the top of basket 40 and terminates at an upper edge 32. A tub cover 33 is attached to the upper edge 32 and extends inwardly over a portion of the top opening 41 of basket 40. The tub cover 33 is cooperable with access opening 15 for providing an access into basket 40.

[0031] Hub 34 includes a central bore 36 which receives output shaft 20. Output shaft 20 is attached at its upper end to a drive gear 38.

[0032] Hub 34 extends through the basin 30 by way of rotary seal arrangement shown schematically at 43 in FIG. 2, and is attached to the basket 40 which includes a spherical portion 42 and a gear box portion 44 at its lower end. Extending over the top of the gear box portion 44 is a curved wall 46 which forms an extension of the spherically shaped walls of spherical portion 42. Curved wall 46 includes a first gear hole 48 and a second gear hole 50 therein. The space below the curved wall 46 comprises a gear box chamber 52 for housing the gear drive to be described hereafter.

[0033] Basket 40 includes a plurality of perforations or apertures 54 in its spherically shaped walls 42 for permitting fluid communication between the interior of basket 40 and the tub 28. Thus as fluid is introduced into the basket 40, the fluid flows through the apertures 54 and enters the tub 28 also. As further depicted in FIG. 2 the web 23, drive motor 18 and the washing assembly are shown suspended from the inside of cabinet 12 by a conventional hung strut suspension system 25 which is of known construction and does not comprise part of the instant invention.

[0034] Agitators or lifters 56, 58 each include a circular peripheral rim 60 and a circular gear 62 which extends circumferencially around the back side of the rim 60. Agitators or lifters 56, 58 are each rotatably mounted to the basket 40 by an agitator mount assembly 64. The agitator mount assembly 64 is shown and described in U.S. Pat. No. 6,220,063, and is adapted to permit the agitators 56, 58 to rotate about the axes identified by the numerals 116, 118 respectively.

[0035] The individual structure of agitator 56 is shown in FIG. 4 and of agitator 58 is shown in FIG. 5. Each agitator 56, 58 includes a concave surface 66 (FIG. 2) which is presented inwardly toward the interior of the tub 40 (FIG. 2). At the center of the concave surface 66 is a central bulge 68, and commencing from this central bulge is a helical rib or baffle 70. Each helical rib 70 includes a central starting point 72 which commences adjacent the rotational axes 116, 118 (FIG. 2) respectively of agitators 56, 58. The helical rib or baffle 70 progresses in an outward radial direction and also in a helical direction to an outer peripheral end 74 which is located adjacent the rim 60 of the agitators 56, 58. Each helical rib 70 includes a first wall 76 and a second wall 78 which are tapered toward one another and which join together at a helical ridge 80. As can be seen in FIG. 2 the first wall 76 is inclined at a less steep angle of inclination than the second wall 78. As can be seen in FIGS. 2, 4 and 5 the ridge 80 commences in the center bottom of agitators 56, 58, and progresses upwardly to the approximate level of rim 60 of agitators 56, 58. Ridge 80 also progresses in a spiral or helix from the center to the outer rim 60 of agitators 56, 58.

[0036] A pair of spaced apart wedges 81 are positioned on the outer edge of each agitator 56, 58 as best seen in FIGS. 4 and 5. Each wedge has a steep surface 83 and a less steep surface 85. The steep surfaces 83 of wedges 81 are facing toward the more steep wall 78 of helical rib 70. These wedges 81 facilitate tumbling of small loads of fabric. Each of the agitators 56, 58 is provided with a plurality of holes 87 that permit flow through of washing fluid.

[0037] Each of the agitators 56, 58 includes a convex back surface 82 which is opposite from the concave surface 66. The convex surface 82 nests against the concave surface 84 of spherical basket 40. The helical direction of the first agitator 56 commences at the center and progresses outward in a clockwise helical direction as viewed in FIG. 4. The helical shape of the rib 70 in the agitator 58 is in the opposite direction, commencing at the center and progressing in a counterclockwise direction toward the outer radial rim 60.

[0038] The spinner rotational position is random. The agitators 56, 58 preferably rotate in a cooperative rotational direction to cause the clothes load to tumble in one direction as indicated by arrows 86, 88 in FIGS. 4 and 5 respectively. When rotating in this direction the less steep walls 76 of the two helical ribs engage the fabrics 134 being washed and lift them upwardly as shown in FIG. 2. At the top of the rotational cycle, the fabrics 134 are dropped downwardly in a central direction, and as they are dropped they turn over in the direction indicated by arrows 120, 122. This creates the turnover necessary in order to adequately clean the fabrics. It is possible however, to reverse the direction of the rotational movement of the agitators 56, 58 so that the steeper wall 78 engages the fabrics and lifts them. This imparts a more aggressive cleaning action. If desired, the agitators 56, 58 can initially be operated in one rotational direction and then reversed.

[0039] Also, the relative positions of the helical ribs 70 in agitators 56, 58 are preferably set so that agitator 58 points at 12 o'clock and the agitator 56 points at 6 o'clock. This places the two helical ribs 70, 180° out of phase with one another and results in further agitation of the fabrics for improved cleaning.

[0040] Referring to FIGS. 2 and 3, a gear assembly 92 is housed within the gear box chamber 52 and includes a first driven gear 94 which directly engages the annular teeth of the drive gear 38. First driven gear 94 is connected to a first agitator gear 96. An idler gear 100 in turn engages gear 104 which has a second agitator gear 106 on its upper surface.

[0041] In operation shaft 20 drives gear 38 in a clockwise direction indicated by arrow 108 (FIG. 3). This rotates gears 94, 100 in the directions shown by arrows 110, 114 respectively. Rotation of gear 94 causes similar rotation of the first agitator gear 96 in the direction indicated by arrow 112. The first agitator gear 96 engages the teeth of circumferencial gear 62 on the back of peripheral rim 60 of agitator 56. This causes rotation of the agitator 56 about its axis formed by the agitator mount assembly 64 in the direction shown by arrow 86.

[0042] Agitator gears 96, 106 rotate in opposite directions, thereby causing the agitators 56, 58 also to rotate in opposite directions. Alternatively, gearing can be provided to cause the agitators 56, 58 to rotate in the same direction if desired or to reverse the rotational direction of agitators 56, 58.

[0043] As can be seen in FIG. 2 the water or washing fluid level 126 is at approximately the level of the agitator mounts 64. The rotation of the two agitators 56, 58 creates a tumbling action of the fabrics being washed within the washing basket 40. This tumbling action is facilitated by the helical ribs or baffles 70.

[0044] The. helical ribs 70 of the present invention provide an improved washing capability. The tumbling action provided by the helical ribs 70 during rotation of the agitators 56, 58 is a gentle action that minimizes damage and wear to delicate fabrics.-Furthermore, the helical ribs 70 cause a lifting of the washing fluid and improve the cleaning of the fabrics within the basket.

[0045] After the washing cycle has been completed, motor 18 is reversed and the reverse rotation of shaft 20 causes the clutch 26 to engage with the hub 34, thereby causing the basket 40 to rotate for its spin cycle. During the spin cycle the washing fluid passes outwardly through apertures 54 due to centrifugal force. The fluid within tub 28 is drained away.

[0046] In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, these are used in a generic and descriptive sense only and not for purposes of limitation. Changes in the form and the proportion of parts as well as in the substitution of equivalents are contemplated as circumstances may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims. 

What is claimed is:
 1. A washing machine comprising: a washing machine cabinet; a wash basket mounted within the washing machine cabinet for rotation about a wash basket axis, the wash basket having an access opening for placing materials to be washed within the wash basket; a first agitator mounted in the basket for rotation about a first agitator axis that extends in a direction different from the wash basket axis; the first agitator having a first helical rib thereon for engaging and agitating the materials to be washed within the wash basket when the first agitator is rotating about the first agitator axis.
 2. A washing machine according to claim 1 comprising a second agitator mounted within the basket for rotation about a second agitator axis extending in a direction different from the wash basket axis and the first agitator axis, the second agitator having a second helical rib thereon for engaging and agitating the materials to be washed within the wash basket when the second agitator is rotating about the second agitator axis.
 3. A washing machine according to claim 2 wherein the first and second agitators each include a concave surface and the first and second helical ribs protrude from the concave surfaces of the first and second agitators respectively.
 4. A washing machine according to claim 3 wherein an agitator drive mechanism is connected to the first and second agitators for driving the first and second agitators in opposite rotational directions.
 5. A washing machine according to claim 4 wherein the first and second helical ribs extend in first and second helical directions that are opposite to one another.
 6. A washing machine according to claim 5 wherein each of the first and second helical ribs commence adjacent the first and second agitator axes respectively and extend in an outward radial helical direction therefrom.
 7. A washing machine according to claim 6 wherein the basket includes a concave interior surface and each of the first and second agitators includes a convex surface opposite from the concave surface thereof, the convex surfaces of the first and second agitators facing toward the concave interior surface of the basket.
 8. A washing machine according to claim 1 wherein the first agitator is circular in shape and includes an outer rim, at least one wedge shaped member being on the agitator adjacent the outer rim for facilitating turnover of fabrics being washed.
 9. An appliance agitator comprising: an agitator member having a concave surface, an opposite convex surface, and a peripheral edge; a helical rib protruding from the concave surface and extending in an outward radial helical direction from a central starting point to an outer end point adjacent the peripheral edge of the agitator member.
 10. An appliance agitator according to claim 9 wherein the peripheral edge extends approximately in a circle.
 11. An appliance agitator according to claim 9 wherein the starting point of the helical rib is at the approximate center of the circle.
 12. An appliance agitator according to claim 9 and further comprising at least one wedge shaped member on the agitator member adjacent the peripheral edge thereof for facilitating turnover of the fabrics being washed.
 13. A washing machine comprising: a cabinet; a washing basket mounted within the cabinet for rotation about a basket axis, the washing basket having a basket cavity and concave interior surface facing toward the basket cavity; a first agitator having a concave surface, an opposite convex surface, and a peripheral edge, the convex surface facing toward the concave interior surface of the washing basket and the concave surface of the first agitator facing toward the basket cavity; the first agitator being mounted for rotation relative to the washing basket about a first agitator axis; a first helical rib protruding from the concave surface of the first agitator, the first helical rib commencing at an inner location and progressing in a helical direction and an outward radial direction therefrom.
 14. A washing machine according to claim 13 and further comprising a second agitator within the basket cavity having a concave surface facing the basket cavity, a convex surface facing the concave surface of the washing basket, and a peripheral edge, the second agitator being mounted for rotation relative to the washing basket about a second agitator axis, a second helical rib protruding from the concave surface of the second agitator.
 15. A washing machine according to claim 14 wherein the second helical rib commences at an inner location and progresses in a helical direction and an outward radial direction therefrom.
 16. A method for operating a washing machine having a basket for containing the fabrics to be washed, and first and second agitators mounted within the basket for rotation about first and second agitator axes respectively, the method comprising: rotating the first and second agitators about the first and second agitator axes respectively; lifting the fabrics being washed with first and second helical ribs on the first and second agitators during rotation of the first and second agitators about the first and second agitator axes respectively; dropping the fabrics from the first and second helical ribs after the first and second helical ribs lift the fabrics whereby the fabrics will turn over and fall within the basket.
 17. A method according to claim 16 and further comprising rotating the first agitator in one direction about the first agitator axis and rotating the second agitator about the second agitator axis in a second direction opposite from the first direction.
 18. A method according to claim 17 and further comprising reversing the rotational direction of the first and second agitators.
 19. A method according to claim 17 wherein the first and second helical ribs each include first and second side walls angling toward one another and being joined together at an elongated helical rib, the first side wall having a first angle of inclination and the second side wall having a second angle of inclination that is steeper than the first angle of inclination, the method further comprising rotating the first and second helical ribs about the first and second agitator axes, respectively in a rotational direction that causes the first side walls of the first and second helical ribs to engage and lift the fabrics.
 20. A method according to claim 19 and further comprising reversing the rotational directions of the first and second helical ribs so that the second side walls of the first and second helical ribs engage and lift the fabrics. 